By Version

Matches a version by the version range. Note that there's no "." before the "*".

Example:=sys-devel/gdb-7.3*

matches: gdb-7.3
matches: gdb-7.3-r1
matches: gdb-7.3.1

NotePlease note that sys-devel/gdb-7.3*, for example, would also match sys-devel/gdb-7.30 (if that actually existed). Also, you cannot avoid this by trying with sys-devel/gdb-7.3.* because 7.3. (with a trailing dot) is not a valid version number.

=category/package-1.23

Matches a version exactly.

Example:=www-client/firefox-7.0

matches: firefox-7.0
does not match: firefox-7.0-r1
does not match: firefox-7.0.1